I will note that while the conquests in Italy (Savoy excepted) were the results of the actions of Napoleon, that was not the case of the conquests in the Rhine and Low Countries. The French had been trying to annex the Low Countries since 1792 and the Cisrhenan Republic arguably could have been restored if you were out to just cancel Napoleon.There is always discussion at what point a conquest is seen as legitimate, but this would be the shortest time I have ever heard of. It is also a problem from a moral point of view: It would leave France with territories conquered in the wars by the same guy the 7th coalition was to end, territories that were forced to provide soldiers for wars not their own. It is a bit like letting a bank robber keep some of his loot as he successfully deposited it in another bank.
The enemy of the Coalition however was less Napoleon and more the legacy of the Revolution; nevertheless, I consider that the removal of the Rhineland and Belgium makes Versailles significantly more lenient than the peace of Vienna. The equivalent would have been creating a Rhenish Republic and then put Poland's western border on the Oder-Neisse.